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Custom Development
Custom Development
We manage the entire development process of a new digital product or the modernisation of an existing one.
A long-term functional, fast, and secure solution
We develop web applications, customer portals, information systems, or mid- to large-scale e-commerce platforms. We build on your designers' work and create a fast, modern, and long-term sustainable solution — from analysis through to implementation and maintenance.
01
We learn about you and your needs
We review all materials you have for the project, find out what you need, who the application will serve, and how it affects other processes and touchpoints.
02
We define goals and expectations
Together with you, we define the goals and expectations the application needs to meet. We also set up a communication strategy between us. We have well-developed and established project management processes that keep you in control of the outcome and budget throughout the development.
03
We propose a suitable approach
We find the ideal combination of technologies and approaches so the application can not only be operated long-term and efficiently, but also integrated with other applications and tools you use.
04
Custom development
We create the solution with an emphasis on speed, security, and long-term sustainability. We thoroughly test and document the application during development so your developers can take it over if needed after completion.
05
Development and maintenance
Launching is not the end of the work. If you want, we'll take care of your application and continue to develop, update, and optimise it. And if something stops working, we address it promptly — even 24/7.
Less than 8 months of operating the new e-shop was enough to pay for 7,000 hours of our work
The Nazuby.cz e-shop ranked among the top 20% of highest-performing e-shops in the world before its redesign, according to metrics published by Wordstream.com. It was therefore absolutely crucial to eliminate the risks associated with replacing the old website with a new one.
+40% profit
After adjusting for natural growth and other factors, profit grew by 24% due to the redesign alone.
+27% revenue
Revenue increased by 27%. Revenue on Nazuby.cz grew by 37% and by 49% on Nazuby.eu.
+33% conversion
Average conversion rate increased by 33%. Specifically +32% on mobile and +38% on desktop.
A partnership that keeps Top-obaly.cz e-shop revenues growing 40% every year
For over ten years we have been continuously improving the e-shop and making it easier for its customers to shop. Our project management is guided by ongoing research, diligent backlog management, regular status calls, and annual roadmaps.
Top 10% worldwide
Top-obaly has averaged a 9% conversion rate since 2015, placing it among the top 10% of highest-performing e-shops in the world.
98% satisfaction
5 stars in overall satisfaction ratings for Top-obaly from 5,958 out of 6,187 verified Heureka.cz user reviews.
+10% user engagement
User engagement on mobile devices increased by 10%, meaning users interact more with content and stay on the site longer.
70th fastest e-shop
Among the 500 most visited e-shops in the Czech Republic, Top-obaly ranks 70th for desktop and 129th for mobile.
We reduced EG.D customer line requests by 20% and saved hundreds of thousands in operating costs
When a customer helpline acts as a guide for clients navigating the website, it means unnecessarily high costs per call. It also points to website shortcomings — in the case of EG.D, that was its complex architecture.
+48% findability
By simplifying the EG.D website structure, working consistently with navigation hubs, and optimising landing pages, we increased the success rate of finding target pages by 48%.
7× more visits
We designed a responsive version of the EG.D website that increased mobile traffic sevenfold in 2020.
+7.2% online submissions
Online form submissions increased by 7.2% compared to postal requests, saving EG.D hundreds of thousands annually.
Modern, fast and sustainable technologies
We don't take technical debt lightly. We keep up with the times and choose technologies that won't age too quickly and for which developers who can work with them are available.
Our proven know-how
Optimisation? Redesign? Simpler system for partners? Digital transformation?
Let's discuss what you're currently facing
Don't want to wait? Call +420 604 122 182 or email tomas.izak@proofreason.com
Tomáš Izák
CEO
„Proof & Reason don't blindly do what the client wants. They think about the brief, keep an eye on details, and give us thoughtful feedback. They're also strong in development and planning. We always know how the project is progressing. When something goes wrong, they acknowledge their mistake. We treat each other as partners. We're truly developing the e-shop together. It's great and fair.“
Ladislav Carda
E-shop and Logistics Manager, Top-obaly.cz
„Working with Proof & Reason is like getting into a Lamborghini. Yes, they're more expensive than the competition, but their approach and especially the results of their work are absolutely top-class.“
Lukáš Pítra
Online Marketing Expert
„What I value about Proof & Reason is their approach and openness. They always met deadlines and everything was transparent. They don't keep their know-how to themselves — they transfer it to the client. I was able to expand the team's capabilities, teach many people to learn and grow. I see that as a major plus.“
Tomáš Kučera
VP Sales & Marketing, Sticky Password
(now Director of Sales, Lingea)
„A quality result can't be achieved overnight. Work on the website design took a long time, but it was worth it. The result speaks for itself.“
Jan Stejskal
CEO, Nazuby.cz
„We wanted to bring a new application to market for installation companies and solar power plant owners, so that anyone could fully harness the potential of renewable energy sources. We knew it wasn't just about the technical perspective, but also the overall design, UX, and marketing strategy. That's why we chose Proof & Reason, which focuses on the overall customer experience and can approach the topic from multiple angles.“
Michal Hrabi
COO, SOLSOL
